From the Mozilla Foundation:
We are committed to supporting developers in making content accessible, no matter an individual’s physical and cognitive abilities and no matter how they access the web. This is why we have been developing a set of useful tools and features called Accessibility Inspector, which allows website owners and developers to test the level of accessibility of their websites and fix the most common issues.
With the release of Firefox 70, we have added several new features that are now available in the Firefox Developer Tools. Here is an overview of the most important tools:
- Check for Keyboard issues: Problems with keyboard navigation and visual focus are a very common source of accessibility problems for various types of users. Firefox now contains a checker for many common keyboard and focus problems and explains how to fix them.
- Contrast: The Accessibility Inspector includes a full-page color contrast checker that checks for all three types of color contrast issues identified by the Web Content Accessibility Guidelines 2.1.
- Color Vision Deficiency Simulator: Firefox now comes with a new tool that simulates seven types of color vision deficiencies (also known as color blindness). This allows developers to see a close approximation of how someone with one of these conditions would see their page. It also allows developers to find out if they have colored something without providing an alternative, so that it can’t be perceived by a color blind user.
- Accessibility Picker: Mouse users can quickly audit elements on a website using the accessibility picker, a tool that highlights an element and shows its properties. Firefox displays an information bar that shows the name, role and color contrast ratio of the element.
Also New Today From Mozilla: “Auditing For Accessibility Problems With Firefox Developer Tools”